Ursodeoxycholic acid-containing agent for treating or preventing presbyopia

ABSTRACT

The present disclosure provides an agent for treating or preventing eye diseases such as presbyopia, comprising, as an active ingredient, ursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid, or an ester thereof, or a pharmaceutically acceptable salt thereof.

TECHNICAL FIELD

The present invention relates to an agent for treating or preventingpresbyopia, comprising ursodeoxycholic acid or an amide conjugate ofursodeoxycholic acid, or an ester thereof, or a pharmaceuticallyacceptable salt thereof as an active ingredient.

BACKGROUND ART

Presbyopia is one of aging phenomena of the eye that begins around theage of 40 and is commonly called aged eyes. According to Non-PatentDocument 1, presbyopia is defined as a disease state in which theaccommodative amplitude decreases with aging (Age-Related Loss ofAccommodation). In order to focus on something near or far away, it isnecessary for the light that enters the eye to be refractedappropriately as it passes through the lens. Therefore, the eye has thefunction of adjusting the thickness of the lens such as contraction ofthe ciliary muscle located near the lens. The ocular tissues involved inthe accommodation include lens, Zinn's zonule, lens capsule, and ciliarymuscle. However, if the function of the ciliary muscle deteriorates dueto aging, or if the lens elasticity (or, viscoelasticity) deteriorates,that is, the lens hardens, it becomes difficult to adjust the thicknessof the lens, and it becomes difficult to focus on objects. Thiscondition is presbyopia.

Reading glasses have been used to cope with presbyopia, but there arerecent reports of research and development of therapeutic agents forpresbyopia. For example, Patent Document 1 discloses that lipoic acidderivatives such as lipoic acid choline ester (alias, EV06, UNR844) areuseful for the treatment of presbyopia. And an eye drop comprisinglipoic acid choline ester is under clinical development in the UnitedStates. Clinical developments of the treatment of presbyopia are alsounderway for an eye drop comprising AGN-199201 and AGN-190584, an eyedrop comprising PRX-100, and an eye drop comprising PresbiDrops (CSF-1).However, the condition of patients with presbyopia is diverse, and anincrease in the types of therapeutic agents for eye diseases is stillstrongly desired so that therapeutic agents can be selected accordingly.

Ursodeoxycholic acid is a compound that promotes bile secretion andinhibits cytokine/chemokine production, and is therefore used in thetreatment of liver diseases (Non-Patent Document 2). However, there isno literature reporting relationship between ursodeoxycholic acid andpresbyopia treatment.

PRIOR ART DOCUMENT Patent Document

Patent Document 1: WO 2010/147957

Non-Patent Document

Non-Patent Document 1: “Atarashii ganka” [A New Ophthalmology], Vol. 28,No. 7, 985-988, 2011

Non-Patent Document 2: Urso® Tablets 50 mg Urso® Tablets 100 mg Packageinsert

The disclosures of the prior art documents cited herein are herebyincorporated by reference in their entirety.

SUMMARY Technical Problem

An object of the present application is to provide a new measure fortreating or preventing presbyopia, which is a very interestingchallenge.

Solution to Problem

As a result of intensive research to solve the above problem, thepresent inventors have found that ursodeoxycholic acid surprisinglyimproves lens elasticity, and thereby have reached the presentapplication.

Specifically, the present disclosure provides the following aspects ofthe invention.

-   [1] An agent for treating or preventing presbyopia comprising, as an    active ingredient, ursodeoxycholic acid or an amide conjugate of    ursodeoxycholic acid, or an ester thereof, or a pharmaceutically    acceptable salt thereof.-   [2] An agent for treating or preventing an eye disease accompanied    by a decrease in lens elasticity comprising, as an active    ingredient, ursodeoxycholic acid or an amide conjugate of    ursodeoxycholic acid, or an ester thereof, or a pharmaceutically    acceptable salt thereof.-   [3] The agent according to [2], wherein the eye disease is    accompanied by a decrease in accommodative function of the eye-   [4] An agent for treating or preventing an eye disease accompanied    by a decrease in accommodative function of the eye comprising, as an    active ingredient, ursodeoxycholic acid or an amide conjugate of    ursodeoxycholic acid, or an ester thereof, or a pharmaceutically    acceptable salt thereof.-   [5] The agent according to any one of [2] to [4], wherein the eye    disease is presbyopia.-   [6] The agent according to any one of [1] to [5], wherein the agent    is for ophthalmic administration.-   [7] The agent according to any one of [1] to [6], wherein the agent    is an eye drop or an eye ointment.-   [8] The agent according to any one of [1] to [7], wherein the amount    of ursodeoxycholic acid or an amide conjugate of ursodeoxycholic    acid, or an ester thereof, or a pharmaceutically acceptable salt    thereof comprised in the agent is 0.00001 to 10% (w/v).-   [9] The agent according to any one of [1] to [8], comprising    ursodeoxycholic acid, tauroursodeoxycholic acid,    glycoursodeoxycholic acid, ursodeoxycholic acid methyl ester,    ursodeoxycholic acid ethyl ester, ursodeoxycholic acid n-propyl    ester, ursodeoxycholic acid isopropyl ester, ursodeoxycholic acid    n-butyl ester, ursodeoxycholic acid isobutyl ester, ursodeoxycholic    acid sec-butyl ester, ursodeoxycholic acid tert-butyl ester,    ursodeoxycholic acid n-pentyl ester, ursodeoxycholic acid n-hexyl    ester, or a pharmaceutically acceptable salt thereof.-   [10] The agent according to any one of [1] to [9], comprising    ursodeoxycholic acid, tauroursodeoxycholic acid,    glycoursodeoxycholic acid, ursodeoxycholic acid methyl ester,    ursodeoxycholic acid ethyl ester, ursodeoxycholic acid n-propyl    ester, ursodeoxycholic acid isopropyl ester, or a pharmaceutically    acceptable salt thereof.-   [11] The agent according to any one of [1] to [10], comprising    ursodeoxycholic acid or a sodium salt thereof.-   [12] The agent according to any one of [1] to [11], further    comprising water, and an additive selected from ethyl pyruvate,    sodium dihydrogenphosphate monohydrate, disodium hydrogenphosphate,    hydroxypropyl methylcellulose, NaCl, and a mixture thereof.-   [13] Use of ursodeoxycholic acid or an amide conjugate of    ursodeoxycholic acid, or an ester thereof, or a pharmaceutically    acceptable salt thereof, in the manufacture of an agent for treating    or preventing presbyopia, an eye disease accompanied by a decrease    in lens elasticity, or an eye disease accompanied by a decrease in    accommodative function of the eye.-   [14] Ursodeoxycholic acid or an amide conjugate of ursodeoxycholic    acid, or an ester thereof, or a pharmaceutically acceptable salt    thereof, for use in the treatment or prevention of presbyopia, an    eye disease accompanied by a decrease in lens elasticity, or an eye    disease accompanied by a decrease in accommodative function of the    eye.-   [15] A method for treating or preventing presbyopia, an eye disease    accompanied by a decrease in lens elasticity, or an eye disease    accompanied by a decrease in accommodative function of the eye,    comprising administering to a subject in need thereof an effective    amount of ursodeoxycholic acid or an amide conjugate of    ursodeoxycholic acid, or an ester thereof, or a pharmaceutically    acceptable salt thereof.

Each of the elements described in the above [1] to [15] may beoptionally selected and combined.

Advantageous Effects of Invention

The therapeutic or prophylactic agent of the present disclosure canimprove the lens elasticity, which is important for lens thicknessadjustment, and is therefore useful in the treatment or prevention ofeye diseases such as presbyopia etc.

Description of Embodiments

Embodiments of the present invention are described in detail below.

The present disclosure provides an agent for treating or preventingpresbyopia comprising, as an active ingredient, ursodeoxycholic acid oran amide conjugate of ursodeoxycholic acid, or an ester thereof, or apharmaceutically acceptable salt thereof (hereinafter sometimes referredto as “the agent of the present invention”). The agent of the presentinvention may be used to improve lens elasticity. In addition, the agentof the present invention may be used to improve eye accommodation.

Ursodeoxycholic acid is a compound represented by formula (1):

(CAS Registration Number: 128-13-2)), also called ursodiol and3α,7β-Dihydroxy-5β-cholan-24-oic acid, and sometimes abbreviated asUDCA.

The amide conjugates of ursodeoxycholic acid which may be comprised inthe agent of the present invention refer to amide conjugates having a—CO—NH— bond which is formed by dehydration condensation of the carboxylgroup of ursodeoxycholic acid with an amino group of an amino compound.

Examples of such amino compound include:

amino acids: for example, alanine, leucine, arginine, lysine,asparagine, methionine, aspartic acid, phenylalanine, cysteine,glutamine, serine, glutamic acid, threonine, glycine, tryptophan,histidine, tyrosine, isoleucine, and valine;

2-aminoadipic acid, 3-aminoadipic acid, 2-aminobutanoic acid,4-aminobutanoic acid, 2,4-diaminobutanoic acid, 2-aminohexanoic acid,6-aminohexanoic acid, 1i-alanine, 2-aminopentanoic acid,2,3-diaminopropanoic acid, 2-aminopimelic acid, 2,6-diaminopimelic acid,cysteic acid, 2,4-diaminobutanoic acid, 2,6-diaminopimelic acid,2,3-diaminopropanoic acid, 4-carboxyglutamic acid, homocysteine,homoserine, homoserine lactone, homoserine lactone, 5-hydroxylysine,allohydroxylysine, alloisoleucine, norleucine, norvaline, ornithine,allothreonine, and thyroxine;

amino acid analogs: e.g., taurine.

Examples of the amide conjugates of ursodeoxycholic acid includetauroursodeoxycholic acid and glycoursodeoxycholic acid.

Tauroursodeoxycholic acid is a compound represented by formula (2):

(CAS Registration Number: 14605-22-2), also called3α,7β-Dihydroxy-5β-cholan-24-oic Acid N-(2-Sulfoethyl)amide, andsometimes abbreviated as TUDCA.

Glycoursodeoxycholic acid is a compound represented by formula (3):

(CAS Registration Number: 64480-66-6), also calledN-(3α,7β-Dihydroxy-5(3-cholan-24-oyl)glycine, and sometimes abbreviatedas GUDCA.

Examples of the esters of ursodeoxycholic acid which may be comprised inthe agent of the present invention include esters which are formed bydehydration condensation of the carboxyl group of ursodeoxycholic acidwith a monohydric alcohol having 1 to 6 carbon atoms (preferably 1 to 4carbon atoms, more preferably 1 to 3 carbon atoms).

Examples of the esters of the amide conjugates of ursodeoxycholic acidwhich may be comprised in the agent of the present invention include,for example, when the amino compound part has carboxyl group(s) and/orsulfonic acid group(s), esters which are formed by dehydrationcondensation of the carboxyl group(s) and/or the sulfonic acid group(s)with monohydric alcohol(s) having 1 to 6 carbon atoms (preferably 1 to 4carbon atoms, more preferably 1 to 3 carbon atoms).

Specific Examples of the esters of ursodeoxycholic acid or the esters ofamide conjugates of ursodeoxycholic acid include methyl esters, ethylesters, n-propyl esters, isopropyl esters, n-butyl esters, isobutylesters, sec-butyl esters, tert-butyl esters, n-pentyl esters, andn-hexyl esters. Preferred examples of the ester include methyl esters,ethyl esters, n-propyl esters, and isopropyl esters.

Other examples include carboxylic acid esters which are formed bydehydration condensation of at least one hydroxyl group ofursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid witha carboxylic acid having 1 to 6 carbon atoms (preferably 1 to 4 carbonatoms, more preferably 2 to 3 carbon atoms). Specific examples of thecarboxylic acid esters include formate esters, acetate esters,propionate esters, isopropionate esters, butyrate esters, isobutyrateesters, pivalate esters, valerate esters, or isovalerate esters.Preferred examples of the carboxylic acid esters include acetate esters.

Salts of ursodeoxycholic acid, salts of amide conjugates ofursodeoxycholic acid, salts of esters of ursodeoxycholic acid, and saltsof esters of amide conjugates of ursodeoxycholic acid, which may becomprised in the agent of the present invention are not particularlylimited as long as they are pharmaceutically acceptable salts. Examplesof pharmaceutically acceptable salts include, inorganic salts such ashydrochlorides, hydrobromides, hydroiodides, nitrates, sulfates,phosphates, etc.; organic acid salts such as acetates,trifluoroacetates, benzoates, oxalates, malonates, succinates, maleates,fumarates, tartrates, citrates, methanesulfonates, ethanesulfonates,trifluoromethanesulfonates, benzenesulfonates, p-toluenesulfonates,glutamates, aspartates, etc.; metal salts such as sodium salts,potassium salts, calcium salts, and magnesium salts, etc.; inorganicsalts such as ammonium salts, etc.; and organic amine salts such astriethylamine salts, guanidine salts, etc. Examples of pharmaceuticallyacceptable salts include preferably sodium salts and potassium salts.

In the agent of the present invention, ursodeoxycholic acid or amideconjugates of ursodeoxycholic acid, or esters thereof, orpharmaceutically acceptable salts thereof may be in the form of hydratesor solvates.

The amount of ursodeoxycholic acid or an amide conjugate ofursodeoxycholic acid, or an ester thereof, or a pharmaceuticallyacceptable salt thereof comprised in the agent of the present inventionis not particularly limited and may be selected from a wide rangedepending on dosage forms etc.

For example, the amount of ursodeoxycholic acid or an amide conjugate ofursodeoxycholic acid, or an ester thereof, or a pharmaceuticallyacceptable salt thereof comprised in the agent of the present inventionis 0.00001 to 10% (w/v), preferably 0.0001 to 5% (w/v), more preferably0.001 to 3% (w/v), even more preferably 0.01 to 2% (w/v), particularlypreferably 0.15 to 1.5% (w/v). An example of the lower limit of theamount is 0.00001% (w/v), a preferable example is 0.0001% (w/v), a morepreferable example is 0.001% (w/v), a further preferable example is0.01% (w/v), a particularly preferable example is 0.1% (w/v), a furtherparticularly preferable example is 0.15% (w/v). An example of the upperlimit of the amount is 10% (w/v), a preferable example is 5% (w/v), amore preferable example is 3% (w/v), a particularly preferable exampleis 2% (w/v), a further particularly preferable example is 1.5% (w/v). Apreferred range of the amount may be indicated by a combination of theabove examples of lower and upper limits.

Further, for example, the amount of ursodeoxycholic acid or an amideconjugate of ursodeoxycholic acid, or an ester thereof, or apharmaceutically acceptable salt thereof comprised in the agent of thepresent invention is 0.00001 to 10% (w/w), preferably 0.0001 to 5%(w/w), more preferably 0.001 to 3% (w/w), even more preferably 0.01 to2% (w/w), particularly preferably 0.15 to 1.5% (w/w). An example of thelower limit of the amount is 0.00001% (w/w), a preferable example is0.0001% (w/w), a more preferable example is 0.001% (w/w), a furtherpreferable example is 0.01% (w/w), a particularly preferable example is0.1% (w/w), and a further preferable example is 0.15% (w/w). An exampleof the upper limit of the amount is 10% (w/w), a preferable example is5% (w/w), a more preferable example is 3% (w/w), a particularlypreferable example is 2% (w/w), and a particularly preferable example is1.5% (w/w). A preferred range of the amount may be indicated by acombination of the above examples of lower and upper limits.

In one embodiment, the amount of ursodeoxycholic acid or an amideconjugate of ursodeoxycholic acid, or an ester thereof, or apharmaceutically acceptable salt thereof comprised in the agent of thepresent invention may be 0.3 to 10% (w/w) (e.g., 0.4 to 5% (w/w), 0.5 to3% (w/w), 0.6 to 1.5% (w/w), 0.8 to 1.3% (w/w)).

In the present disclosure, “% (w/v)” means the mass (g) of the activeingredient (ursodeoxycholic acid and amide conjugate(s) ofursodeoxycholic acid, and ester(s) thereof, and pharmaceuticallyacceptable salt(s) thereof) or an additive (surfactant, etc.) comprisedin 100 mL of an agent. For example, “0.01% (w/v) of ursodeoxycholicacid” means that the amount of ursodeoxycholic acid comprised in 100 mLof an agent is 0.01 g.

In the present disclosure, “% (w/w)” means the mass (g) of the activeingredient (ursodeoxycholic acid and amide conjugate(s) ofursodeoxycholic acid, and ester(s) thereof, and pharmaceuticallyacceptable salt(s) thereof) or an additive (surfactant, etc.) comprisedin 100 g of an agent. For example, “0.01% (w/w) of ursodeoxycholic acid”means that the amount of ursodeoxycholic acid comprised in 100 g of anagent is 0.01 g.

When ursodeoxycholic acid, an amide conjugate of ursodeoxycholic acid,an ester of ursodeoxycholic acid, or an ester of an amide conjugate ofursodeoxycholic acid are in the form of salt, or in the form of hydrateor solvate (including the form of hydrate or solvate of the salt), theamount of ursodeoxycholic acid or an amide conjugate of ursodeoxycholicacid, or an ester thereof, or a pharmaceutically acceptable salt thereofcomprised in the agent may mean the mass of the salt, hydrate, orsolvate (including the hydrate or solvate of the salt) added into theagent, or may mean the mass converted as a free form of ursodeoxycholicacid, the amide conjugate of ursodeoxycholic acid or the ester thereof,preferably may mean the mass converted as a free form of ursodeoxycholicacid, the amide conjugate of ursodeoxycholic acid, or the ester thereof.

In this disclosure, the term “presbyopia” means a symptom/disease thatis determined to be presbyopia based on general criteria used by aphysician or professional.

For example, diagnostic criteria for presbyopia include:

Decreased near vision is noticed as a subjective symptom in a binocularvision test, and a binocular daily life visual acuity, which is abinocular distant visual acuity measured under the same condition asdaily life, is less than 0.4 at 40 cm distance(clinical presbyopia);and/or

With or without subjective symptoms, under unilateral best-correctionwhere a corrected visual acuity of one eye is equal to or more than 1.0(decimal visual acuity), accommodative amplitude is less than 2.5Diopters” (medical presbyopia).

However, if an accommodometer etc. is not available, a simple criterionwherein a visual acuity at 40 cm is less than 0.4 may be used.

In the present disclosure, the term “an eye disease accompanied by adecrease in lens elasticity” refers to an eye disease considered in thefield of ophthalmology to be accompanied by a decrease in lenselasticity, including, for example, presbyopia (e.g., presbyopia due toaging), and a hardening of the lens induced by drugs and the like.

In the present disclosure, the term “accommodation function of the eye”refers to an eye function that automatically focuses on distant and/ornear objects. The term “an eye disease accompanied by a decrease inaccommodative function of the eye” refers to an eye disease consideredin the field of ophthalmology to be accompanied by a decrease inaccommodative function of the eye, including, for example, presbyopia(e.g., presbyopia due to aging), and a hardening of the lens induced bydrugs etc., and decreased accommodation function induced by seeing nearobjects for a long time.

The efficacy of the agent of the present invention may be evaluated, forexample, as an increase in “accommodative amplitude of the eye”. Theaccommodative amplitude of the eye can be measured as a Diopter (D)which can be determined by the following expression 1:

Diopter(D)=1/Near Point Distance(m)   (Expression 1).

In general, the accommodative amplitude of the eye is greater than 10diopters at 10 years, then gradually decreases to about 3 diopters atabout 45 years and is almost lost at about 60 years. When theaccommodative amplitude decreases to about 3 diopters, it becomesdifficult to focus on near objects (about 30 cm) in daily life, andsubjective symptoms of presbyopia appear.

The efficacy of the agent of the present invention may be evaluated, forexample, as an improvement in “visual acuity”. The visual acuity can bemeasured as near visual acuity (uncorrected visual acuity,distance-corrected near visual acuity, corrected visual acuity) and canbe measured by using decimal visual acuity, fractional visual acuity, orlogMAR.

In general, when near visual acuity which is defined to be measured atabout 40 cm decreases to below 0.4, it causes difficulty in seeing nearobjects, and subjective symptoms of presbyopia appear. The agent of thepresent invention may be used to improve near visual acuity (e.g.,distance-corrected near visual acuity).

The agent of the invention may begin to exhibit an efficacy within oneyear, preferably within six months, more preferably within one month,more preferably within one week, and most preferably within one dayafter the administration. Further, once an efficacy is exerted, theefficacy may be exerted continuously until after one day, preferablyuntil after one week, more preferably until after one month, morepreferably until after six months, particularly preferably until afterone year, and most preferably until after three years.

The agent of the present invention may be administered, for example, soas to increase the accommodative amplitude of the eye by at least about0.5 diopters (preferably at least about 1 diopter, more preferably atleast about 1.5 diopters, more preferably at least about 2 diopters,even more preferably at least about 3 diopters, and still morepreferably at least about 4 diopters, particularly preferably at leastabout 5 diopters, and still more preferably at least about 10 diopters).

The agent of the present invention may be administered, for example, soas to increase distance-corrected near visual acuity (DCNVA) by at leastabout 0.5 logMAR (preferably about at least 1.0 logMAR, more preferablyabout at least 1.5 logMAR, even more preferably about 2.0 logMAR, evenmore preferably about 3.0 logMAR, particularly preferably about 4.0logMAR, particularly preferably about 5.0 logMAR, and even morepreferably about 6.0 logMAR).

The term “distance-corrected near visual acuity” generally refers tonear visual acuity measured with distance visual acuity corrected to 0.0logMAR (decimal visual acuity of 1.0 or more).

The agent of the present invention may be administered, for example, soas to restore the accommodative amplitude of the eye to at least about0.5 diopters (preferably at least about 1 diopter, more preferably atleast about 1.5 diopters, more preferably at least about 2 diopters,more preferably at least about 3 diopters, particularly preferably atleast about 4 diopters, particularly preferably at least about 5diopters, and still more preferably at least about 10 diopters).

The agent of the present invention may be administered, for example, soas to restore the distance-corrected near visual acuity (DCNVA) to atleast about 0.5 logMAR (preferably at least about 1.0 logMAR, morepreferably at least about 1.5 logMAR, even more preferably about 2.0logMAR, even more preferably about 3.0 logMAR, particularly preferablyabout 4.0 logMAR, particularly preferably about 5.0 logMAR, and evenmore preferably about 6.0 logMAR).

In the present disclosure, the treatment or prevention of presbyopiaincludes increasing an elasticity of the lens, improving an ability toadjust a thickness of lens, and/or improving an accommodative functionof the eye.

Although subjective symptoms of presbyopia generally appear at about 45years of age as mentioned above, age-related decline in eyeaccommodation has been progressing since teens. The agent of the presentinvention may be used after the subjective symptoms of presbyopiaappear, and may be used to prevent and/or delay progression ofpresbyopia before the subjective symptoms of presbyopia appear.

The subjects of administration of the agent of the present invention aremammals including livestock such as cattle and pigs; rabbits, monkeys,dogs, cats, and humans, preferably humans.

In this disclosure, “treatment (treating)” and “prevention (preventing)”may include, in addition to treating and preventing a disease,alleviating symptoms of the disease, delaying progression of thedisease, suppressing symptoms of the disease, and inducing improvementin symptoms of the disease.

The agent of the present invention may be administered orally orparenterally (e.g., ocularly, nasally, transdermally, transmucosally, byinjection, etc.). The agent of the present invention may be prepared inthe usual manner in the art by mixing the active ingredient with, forexample, one or more pharmaceutically acceptable additives, for example,in the form of oral preparations such as tablets, capsules, granules,powders, lozenges, syrups, emulsions, suspensions, and the like, orparenteral preparations such as eye drops, ophthalmic ointments,injections, suppositories, nasal preparations, and the like. Preferredformulations of the agent of the present invention include eye drops(e.g., ophthalmic suspensions) and eye ointments from the viewpoint ofgreater efficacy of the agents of the invention.

Pharmaceutically acceptable additives that may be comprised in the agentof the present invention are not particularly limited and may beselected as appropriate according to the route of administration,formulation, etc. Examples of such pharmaceutically acceptable additivesinclude, for example, surfactants, buffers, tonicity agents,stabilizers, preservatives, antioxidants, thickeners, solubilizingagents, suspending agents, bases, solvents, pH adjusters, excipients,disintegrating agents, binders, fluidizers, lubricants, preservatives,antioxidants, coloring agents, sweetening agents, and the like.

When the agent of the present invention is an eye drop, examples ofadditives that may be used include surfactants, buffers, tonicityagents, stabilizers, preservatives, antioxidants, thickeners, solvents,pH adjusters, and the like.

Examples of surfactants include cationic surfactants, anionicsurfactants, nonionic surfactants and the like.

When a surfactant is added to the agent of the present invention, theamount of the surfactant comprised in the agent may be appropriatelyadjusted depending on the type of the surfactant, etc., and ispreferably, for example, 0.01 to 1% (w/v).

Examples of buffers include phosphoric acid or salts thereof, which maybe hydrates or solvates thereof.

Examples of the phosphoric acid or salts thereof include phosphoricacid, trisodium phosphate, sodium dihydrogenphosphate, sodium hydrogenphosphate (disodium hydrogenphosphate) and the like, which may behydrates thereof.

When a buffer is added to the agent of the present invention, the amountof the buffer comprised in the agent may be appropriately adjusteddepending on the type of the buffer, etc., but for example, 0.001 to 10%(w/v) is preferable, and 0.01 to 5% (w/v) is more preferable. Two ormore kinds of buffers may be used together.

Examples of tonicity agents include ionic tonicity agents and nonionictonicity agents. Examples of the ionic tonicity agents include sodiumchloride and the like.

When a tonicity agent is added to the agent of the present invention,the amount of the tonicity agent comprised in the agent may beappropriately adjusted according to the type of the tonicity agent orthe like, but for example, 0.001 to 10% (w/v) is preferable, and 0.01%to 5% (w/v) is more preferable.

Examples of thickeners include hydroxypropyl methylcellulose and thelike.

When a thickener is added to the agent of the present invention, theamount of the thickener may be appropriately adjusted according to thetype of the thickener or the like, but for example, 0.001 to 5% (w/v) ispreferable, and 0.01% to 3% (w/v) is more preferable.

When the agent of the present invention is an aqueous formulation (e.g.,eye drops), the pH is preferably 4 to 8 and more preferably 5 to 7.

Examples of solvents include water, physiological saline and the like.

Examples of the agent of the present invention which is an aqueouspreparation (e.g., eye drop) include aqueous preparations comprisingursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid, oran ester thereof, or a pharmaceutically acceptable salt thereof, water,and an additive selected from ethyl pyruvate, sodium dihydrogenphosphatemonohydrate (NaH₂PO₄H₂O), disodium hydrogenphosphate (Na₂HPO₄),hydroxypropyl methylcellulose, NaCl, and a mixture thereof. Here, said“a mixture thereof” means any combination of the listed specificadditives.

As used herein, the term “an effective amount” is the amount of theactive ingredient required to provide a patient benefit in the symptomsof a disease.

A dosage and administration of the agent of the present invention is notparticularly limited as long as the dosage and administration aresufficient to achieve the desired medicinal effect, and may beappropriately selected according to the symptoms of the disease, the ageand weight of the patient, the dosage form of the agent, etc.

For example, in the case of eye drops, a single dose of 1 to 5 drops(preferably 1 to 3 drops, more preferably 1 to 2 drops, particularlypreferably 1 drop) may be instilled 1 to 4 times per day (preferably 1to 3 times per day, more preferably 1 to 2 times per day, particularlypreferably once per day), every day or at an interval of from one day toone week. The “one drop” is usually about 0.01 to about 0.1 mL,preferably about 0.015 to about 0.07 mL, more preferably about 0.02 toabout 0.05 mL, and particularly preferably about 0.03 mL.

In one embodiment, the agent of the present invention have an immediateeffect on presbyopia, an eye disease accompanied by a decrease in lenselasticity, or an eye disease accompanied by a decrease in accommodativefunction of the eye, for example, compared to EV06.

The duration of administration of the agent of the present invention maybe determined by a physician or professional.

In one embodiment, the agent of the present invention may be anophthalmic administration agent such as an eye drop (e.g., a suspension)and an eye ointment, and may be used continuously for at least 2 days,at least 3 days, at least 7 days, at least 10 days.

In one embodiment, the agent of the present invention may beadministered at least once (e.g., at least twice, at least three times)a day.

In one embodiment, the agent of the present invention, when administeredto the eye, may be less irritating to the eye while having an effect onpresbyopia, an eye disease accompanied by a decrease in lens elasticity,or an eye disease accompanied by a decrease in accommodative function ofthe eye.

EXAMPLES

The results of pharmacological tests are shown below for a betterunderstanding of the present invention and are not intended to limit thescope of the present invention.

[Pharmacological Test 1]

The effect of lipoic acid choline ester (EV06) on the lens elasticitywas examined. The tests were conducted with reference to the methodsdescribed in InvestOphthalmol Vis Sci, 57, 2851-2863, 2016. EV06 is acompound represented by the following formula (2):

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, and 0.5% (w/v) of NaCl was prepared.

2) Preparation of EVO6 Sample

EVO6 was sonicated with the addition of the vehicle to prepare a 5%(w/v) suspension. The resulting 5% (w/v) suspension was diluted with thevehicle to prepare a 1.5% (w/v) solution. Further, the resulting 1.5%(w/v) solution was diluted with the vehicle to prepare a 0.5% (w/v)solution. The total amount of each sample to be used in one day wasprepared before use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into the right eye of    8-month-old C57BL/6J mice with a Pipetman 3 times per day (around    9:00, 13:00 and 17:00) for 15 to 17 days.-   2) After the final instillation, the mice were euthanized by carbon    dioxide inhalation, and then the eyeballs were extracted and rinsed    with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HESS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22×22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below.

The mean of the vehicle control group was based on 6 eyes and the meanof each EVO6 sample group was based on 12 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each EVO6 sample group−Mean change in lens diameter ofVehicle control group   (Equation 2)

(Results)

The results are shown in Table 1.

TABLE 1 Lens elasticity improvement (μm) 0.5% EV06 sample 28.8 1.5% EV06sample 47.3 5% EV06 sample 48.7

As shown in Table 1, all of the 0.5%, 1.5%, and 5% EVO6 groups showedthe increased lens diameter compared with the vehicle control group,which confirms that EVO6 has an elasticity improving effect.

[Pharmacological Test 2]

The effect of sodium ursodeoxycholate on the lens elasticity wasexamined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2) Preparation of Sodium Ursodeoxycholate Sample

Sodium ursodeoxycholate was sonicated with the addition of the vehicleto prepare a 1.5% (w/v) suspension. The resulting 1.5% (w/v) suspensionwas diluted with the vehicle to prepare a 0.5% (w/v) suspension.Further, the resulting 0.5% (w/v) suspension was diluted with thevehicle to prepare a 0.15% (w/v) suspension. The total amount of eachsample to be used in one day was prepared before use.

3) Preparation of EVO6 Sample

EVO6 was sonicated with the addition of the vehicle to prepare a 1.5%(w/v) solution. The total amount of the sample to be used in one day wasprepared before use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into the right eye of    8-month-old C57BL/6J mice with a Pipetman 3 times per day (around    9:00, 13:00 and 17:00) for 12 to 15 days.-   2) After the final instillation, the mice were euthanized by carbon    dioxide inhalation, and then the eyeballs were extracted and rinsed    with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HBSS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22×22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. The mean of    the vehicle control group was based on 5 eyes, the mean of each    sodium ursodeoxycholate sample group was based on 10 eyes, and the    mean of the EVO6 sample group was based on 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group   (Equation 2)

(Results)

The results are shown in Table 2.

TABLE 2 Lens elasticity improvement (μm) 0.15% sodium 26.5ursodeoxycholate sample 0.5% sodium 34.8 ursodeoxycholate sample 1.5%sodium 44.7 ursodeoxycholate sample 1.5% EV06 sample 38.2

As shown in Table 2, all of the 0.15%, 0.5%, and 1.5% sodiumursodeoxycholate sample groups showed a potent lens elasticity improvingeffect. The lens elasticity improving effect of the 1.5% sample groupwas stronger than that of EVO6 at the same concentration.

[Pharmacological Test 3]

The effect of ursodeoxycholic acid (free form) on the lens elasticitywas examined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, and 0.5% (w/v) of NaCl was prepared.

2) Preparation of Ursodeoxycholic Acid Sample

Ursodeoxycholic acid was sonicated with the addition of the vehicle toprepare a 1.5% (w/v) suspension. The resulting 1.5% (w/v) suspension wasdiluted with the vehicle to prepare a 0.5% (w/v) suspension. Further,the resulting 0.5% (w/v) suspension was diluted with the vehicle toprepare a 0.15% (w/v) suspension. The total amount of each sample to beused in one day was prepared before use.

3) Preparation of EVO6 Sample

EVO6 was sonicated with the addition of the vehicle to prepare a 1.5%(w/v) solution. The total amount of the sample to be used in one day wasprepared before use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into the right eye of    8-month-old C57BL/6J mice with a Pipetman 3 times per day (around    9:00, 13:00 and 17:00) for 12 to 15 days.-   2) After the final instillation, the mice were euthanized by carbon    dioxide inhalation, and then the eyeballs were extracted and rinsed    with Hank's balanced salt solution (HESS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HESS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22>22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. The mean of    the vehicle control group was based on 5 eyes, the mean of each    ursodeoxycholic acid sample group was based on 10 eyes, and the mean    of the EVO6 sample group was based on 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group

(Results)

The results are shown in Table 3.

TABLE 3 Lens elasticity improvement (μm) 0.15% ursodeoxycholic 31.8 acidsample 0.5% ursodeoxycholic 39.4 acid sample 1.5% ursodeoxycholic 59.9acid sample 1.5% EV06 sample 42.5

As shown in Table 3, all of the 0.15%, 0.5%, and 1.5% sodiumursodeoxycholate sample groups showed a potent lens elasticity improvingeffect. The lens elasticity improving effect of the 1.5% sample groupwas stronger than that of EVO6 at the same concentration.

[Pharmacological Test 4]

The effect of once-daily instillation of ursodeoxycholic acid for 2weeks on the lens elasticity was examined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2) Preparation of Ursodeoxycholic Acid Sample

Ursodeoxycholic acid was sonicated with the addition of the vehicle toprepare a 3.0% (w/v) suspension. The resulting 3.0% (w/v) suspension wasdiluted with the vehicle to prepare a 1.0% (w/v) suspension. Further,the resulting 1.0% (w/v) suspension was diluted with the vehicle toprepare a 0.3% (w/v) suspension. The total amount of each sample to beused in one day was prepared before use.

3) Preparation of EVO6 Sample

EVO6 was sonicated with the addition of the vehicle to prepare a 1.5%(w/v) solution. The total amount of the sample to be used in one day wasprepared before use.

(Test method)

-   1) Each test sample (2.5 μL/eye) was instilled into the right eye of    8-month-old C57BL/6J mice with a Pipetman once per day (QD; around    9:00), twice per day (BID; around 9:00 and 17:00), or 3 times per    day (TID; around 9:00, 13:00 and 17:00) for 14 days.-   2) After the final instillation, the mice were euthanized by carbon    dioxide inhalation, and then the eyeballs were extracted and rinsed    with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HBSS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22×22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. The mean of    the vehicle control group was based on 5 eyes, the mean of each    ursodeoxycholic acid sample group was based on 10 eyes, and the mean    of each EVO6 sample group was based on 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group

(Results)

The results are shown in Table 4.

TABLE 4 Lens improvement elasticity (μm) 0.3% ursodeoxycholic acidsample 2.8 (QD) 1% ursodeoxycholic acid sample 28.1 (QD) 3%ursodeoxycholic acid sample 30.4 (QD) 1.5% EV06 sample (QD) −3.6 1.5%EV06 sample(BID) 15.7 1.5% EV06 sample(TID) 29.5

As shown in Table 4, 1% ursodeoxycholic acid sample and 3%ursodeoxycholic acid sample caused a potent lens elasticity improvementwhen they were instilled once-daily while 1.5% EVO6 sample instilledonce-daily had no effect, which indicates that ursodeoxycholic acid hasa more potent lens elasticity improvement effect compared with EV06.

[Pharmacological Test 5]

The effect of 1% ursodeoxycholic acid instilled once-daily for 1, 3, 7,10, or 14 days on the lens elasticity was examined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2) Preparation of 1% ursodeoxycholic acid sample

Ursodeoxycholic acid was sonicated with the addition of the vehicle toprepare a 1.0% (w/v) suspension. The total amount of the sample to beused in one day was prepared before use.

(Test Method)

-   1) The test sample (2.5 pL/eye) was instilled into both eyes of    8-month-old C57BL/6J mice with a Pipetman once per day (QD; around    13:30) for 1, 3, 7, 10, or 14 days.-   2) Twenty-four hours after the final instillation, the mice were    euthanized by carbon dioxide inhalation, and then the eyeballs were    extracted and rinsed with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HBSS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22>22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. Each mean of    the untreated group and each ursodeoxycholic acid sample group was    based on 9 or 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofUntreated group   (Equation 2)

(Results)

The results are shown in Table 5.

TABLE 5 Lens elasticity improvement (μm) 1% ursodeoxycholic acid sample9.6 (1 day) 1% ursodeoxycholic acid sample 21.1 (3 days) 1%ursodeoxycholic acid sample 27.4 (7 days) 1% ursodeoxycholic acid sample38.1 (10 days) 1% ursodeoxycholic acid sample 34.2 (14 days)

As shown in Table 5, the 1% ursodeoxycholic acid sample instilledonce-daily caused improvement in the lens elasticity according to theincrease of the duration of instillation, and showed definitely animprovement in lens elasticity after instillation for 3 days. Thissuggests that ursodeoxycholic acid can early cause the effect.

[Pharmacological Test 6]

The effect of once-daily instillation of ursodeoxycholic acid methylester for 7 days on the lens elasticity was examined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2) Preparation of Ursodeoxycholic Acid Methyl Ester Sample

Ursodeoxycholic acid methyl ester was sonicated with the addition of thevehicle to prepare a 0.3% (w/v) suspension, a 1.0% (w/v) suspension anda 3.0% (w/v) suspension. The total amount of each sample to be used inone day was prepared before use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into both eyes of    7-month-old C57BL/6J mice with a Pipetman once per day (QD; around    13:30) for 7 days.-   2) Twenty-four hours after the final instillation, the mice were    euthanized by carbon dioxide inhalation, and then the eyeballs were    extracted and rinsed with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HBSS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning® 22×22 mm Square) was placed on    the lens, and an image in which the thickness of the lens changed    due to the weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. Each mean of    the vehicle control group and each ursodeoxycholic acid methyl ester    sample group was based on 9 or 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group   (Equation 2)

(Results)

The results are shown in Table 6.

TABLE 6 Lens elasticity improvement (μm) 0.3% ursodeoxycholic acid 13.2methyl ester sample 1% ursodeoxycholic acid 33.0 methyl ester sample 3%ursodeoxycholic acid 46.5 methyl ester sample

As shown in Table 6, 1% ursodeoxycholic acid methyl ester sample and 3%ursodeoxycholic acid methyl ester sample caused a potent lens elasticityimprovement even when they were instilled once-daily. These resultssuggest that ursodeoxycholic acid methyl ester may also have a morepotent lens elasticity improvement effect compared with 1.5% EV06.

[Pharmacological Test 7]

The effect of tauroursodeoxycholic acid instilled once-daily for 7 dayson the lens elasticity was examined.

(Preparation of Test Sample) 1) Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2) Preparation of Tauroursodeoxycholic Acid Sample

Tauroursodeoxycholic acid was dissolved with the addition of the vehicleto prepare a 1.0% (w/v) solution. The total amount of each sample to beused in one day was prepared before use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into both eyes of    7-month-old C57BL/6J mice with a Pipetman once per day (QD; around    13:30) for 7 days.-   2) Twenty-four hours after the final instillation, the mice were    euthanized by carbon dioxide inhalation, and then the eyeballs were    extracted and rinsed with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HBSS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass (Corning (registered trade mark) 22×22 mm    Square) was placed on the lens, and an image in which the thickness    of the lens changed due to the weight was similarly captured (Image    b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. Each mean of    the vehicle control group and the tauroursodeoxycholic acid sample    group was based on 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group   (Equation 2)

(Results)

The results are shown in Table 7.

TABLE 7 Lens elasticity improvement (μm) 1% tauroursodeoxycholic 29.7acid sample

The 1% tauroursodeoxycholic acid sample instilled once-daily caused apotent lens elasticity improvement as shown in Table 7 while the 1.5%EVO6 sample instilled once-daily for 14 days had no effect as shown inTable 4, which suggests that tauroursodeoxycholic acid has a more potentlens elasticity improvement effect than EV06.

[Pharmacological Test 8]

The effect of glycoursodeoxycholic acid instilled once-daily for 7 dayson the lens elasticity was examined.

(Preparation of Test Sample) 1)Preparation of Vehicle

A vehicle comprising 0.1% (w/v) of ethyl pyruvate, 0.269% (w/v) ofsodium dihydrogenphosphate monohydrate (NaH₂PO₄H₂O), 0.433% (w/v) ofdisodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) of hydroxypropylmethylcellulose, 0.5% (w/v) of NaCl was prepared.

2)Preparation of Glycoursodeoxycholic Acid Sample

Glycoursodeoxycholic acid was sonicated with the addition of the vehicleto prepare a 1.0% (w/v) suspension.

The total amount of each sample to be used in one day was preparedbefore use.

(Test Method)

-   1) Each test sample (2.5 μL/eye) was instilled into both eyes of    8-month-old C57BL/6J mice with a Pipetman once per day (QD; around    13:30) for 7 days.-   2) Twenty-four hours after the final instillation, the mice were    euthanized by carbon dioxide inhalation, and then the eyeballs were    extracted and rinsed with Hank's balanced salt solution (HBSS).-   3) The sclera near the optic nerve was cut with a razor, the lens    was removed through the incision, and the removed lens was immersed    in HESS.-   4) The lens was placed on a glass slide, and an all-in-one    fluorescence microscope BZ-9000 (Keyence) was used to capture an    image of the lens (Image a).-   5) Next, one cover glass® 22×22 mm Square) was placed on the lens,    and an image in which the thickness of the lens changed due to the    weight was similarly captured (Image b).-   6) A change in the lens diameter was calculated from Equation 1    wherein the lens diameter of Image a is subtracted from the lens    diameter of Image b, as described below. Then, the lens elasticity    improvement of each sample group compared with the vehicle control    group was calculated from Equation 2 described below. Each mean of    the vehicle control group and the glycoursodeoxycholic acid sample    group was based on 9 to 10 eyes.

Change in lens diameter=Lens diameter in Image b of each testsample−Lens diameter in Image a of each test sample   (Equation 1)

Lens elasticity improvement of each sample group=Mean change in lensdiameter of each Test sample group−Mean change in lens diameter ofVehicle control group   (Equation 2)

(Results)

The results are shown in Table 8.

TABLE 8 Lens elasticity improvement (μm) 1% glycoursodeoxycholic 20.1acid sample

The 1% glycoursodeoxycholic acid sample instilled once-daily caused apotent lens elasticity improvement as shown in Table 8 while the 1.5%EVO6 sample instilled once-daily for 14 days had no effect as shown inTable 4, which suggests that glycoursodeoxycholic acid has a more potentlens elasticity improvement effect than EV06.

[Ocular Irritation Test] (Preparation of Sample)

A vehicle (aqueous solution) comprising 0.1% (w/v) of ethyl pyruvate,0.269% (w/v) of sodium dihydrogenphosphate-monohydrate (NaH₂PO₄.H₂O),0.433% (w/v) of disodium hydrogenphosphate (Na₂HPO₄), 0.2% (w/v) ofhydroxypropyl methylcellulose, 0.5% (w/v) of NaCl was prepared.

(Test Method)

Group treated with an ophthalmic suspension of ursodeoxycholic acid 1%(w/v), 3% (w/v), and 10% (w/v) ursodeoxycholic acid ophthalmicsuspensions were prepared in the same manner as in the abovepharmacological tests. These ophthalmic suspensions and the vehicle wereeach instilled into the left eye of Japanese White rabbits at a dose of50 μL/eye with pipette twice per day at a 6-hour interval for 2 weeks.One hour after the final instillation, ocular irritation of anteriorsegment of the eye was evaluated according to the McDonald-Shadduckmethod, and the lens was observed. The contralateral eye was untreated.The ocular irritation of anterior segment of the eye was scoredaccording to the following criteria: +1: mild; +2: moderate; +3: severe.

(Test Result)

The test results are shown in Table 9. After the 2 week-repeatedinstillation, no abnormal findings were observed in eyes treated withthe ophthalmic suspensions of ursodeoxycholic acid in the observation ofocular irritation of anterior segment of the eye and lens observation.Histopathological examination of the eyes showed no abnormal findings.

TABLE 9 1% Urso- 3% Urso- 10% Urso- deoxy- deoxy- deoxy- Ophthalmiccholic cholic cholic suspension Vehicle acid acid acid Number of animals3 3 3 3 Ocular Conjunctival — — — — irritation hyperemia of anteriorPalpebral — — — — segment of conjunctival the eye ¹⁾ edema Discharge — —— — Corneal — — — — opacity Corneal — — — — epithelial disorder Lens — —— — Histopathological — — — — examination —: No noteworthy findings, ¹⁾Score of the instilled left eye and the number of the eye, 1 hour afterthe final instillation are described.

(Discussion)

It is shown that the ophthalmic suspensions of ursodeoxycholic acid ishighly safe.

INDUSTRIAL APPLICABILITY

The agent of the present invention is useful for treating or preventingeye diseases such as presbyopia etc.

1. (canceled)
 2. (canceled)
 3. (canceled)
 4. (canceled)
 5. (canceled) 6.(canceled)
 7. (canceled)
 8. (canceled)
 9. (canceled)
 10. (canceled) 11.(canceled)
 12. (canceled)
 13. A method for treating or preventingpresbyopia, comprising administering to a subject in need thereof aneffective amount of ursodeoxycholic acid or an amide conjugate ofursodeoxycholic acid, or an ester thereof, or a pharmaceuticallyacceptable salt thereof.
 14. The method according to claim 13, whereinthe ursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid,or an ester thereof, or a pharmaceutically acceptable salt thereof, isadministered ophthalmically.
 15. The method according to claim 13,wherein the ursodeoxycholic acid or an amide conjugate ofursodeoxycholic acid, or an ester thereof, or a pharmaceuticallyacceptable salt thereof, is administered as an eye drop or an eyeointment.
 16. The method according to claim 15, wherein the amount ofursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid, oran ester thereof, or a pharmaceutically acceptable salt thereof,comprised in the eye drop or the eye ointment is 0.00001 to 10% (w/v).17. The method according to claim 13, wherein the ursodeoxycholic acidor an amide conjugate of ursodeoxycholic acid, or an ester thereof, or apharmaceutically acceptable salt thereof, is selected fromursodeoxycholic acid, tauroursodeoxycholic acid, glycoursodeoxycholicacid, ursodeoxycholic acid methyl ester, ursodeoxycholic acid ethylester, ursodeoxycholic acid n-propyl ester, ursodeoxycholic acidisopropyl ester, ursodeoxycholic acid n-butyl ester, ursodeoxycholicacid isobutyl ester, ursodeoxycholic acid sec-butyl ester,ursodeoxycholic acid tent-butyl ester, ursodeoxycholic acid n-pentylester, ursodeoxycholic acid n-hexyl ester, or a pharmaceuticallyacceptable salt thereof.
 18. The method according to claim 13, whereinthe ursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid,or an ester thereof, or a pharmaceutically acceptable salt thereof, isselected from ursodeoxycholic acid, tauroursodeoxycholic acid,glycoursodeoxycholic acid, ursodeoxycholic acid methyl ester,ursodeoxycholic acid ethyl ester, ursodeoxycholic acid n-propyl ester,ursodeoxycholic acid isopropyl ester, or a pharmaceutically acceptablesalt thereof.
 19. The method according to claim 13, wherein theursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid, oran ester thereof, or a pharmaceutically acceptable salt thereof, isursodeoxycholic acid or a sodium salt thereof.
 20. The method accordingto claim 15, wherein the eye drop or the eye ointment comprises water,and an additive selected from ethyl pyruvate, sodium dihydrogenphosphatemonohydrate, disodium hydrogenphosphate, hydroxypropyl methylcellulose,NaCl, or a mixture thereof.
 21. A method for treating or preventing aneye disease accompanied by a decrease in lens elasticity, comprisingadministering to a subject in need thereof an effective amount ofursodeoxycholic acid or an amide conjugate of ursodeoxycholic acid, oran ester thereof, or a pharmaceutically acceptable salt thereof.
 22. Amethod for treating or preventing an eye disease accompanied by adecrease in accommodative function of the eye, comprising administeringto a subject in need thereof an effective amount of ursodeoxycholic acidor an amide conjugate of ursodeoxycholic acid, or an ester thereof, or apharmaceutically acceptable salt thereof.